Almost 300,000 nurses will start voting today on whether to continue strikes in their long-running battle over pay and staffing.
Members of the Royal College of Nursing in England are being asked to renew their mandate for industrial action until the end of the year.
The RCN says members should vote to continue strikes as this will increase pressure on ministers to improve the pay offer that was rejected in April.
RCN general secretary Pat Cullen said: “Once again, we have been forced to ask our members if they want to take to the picket lines in their fight for fair pay.
“This is unfinished business and the government can get it resolved without the need for more strike action.
“Ministers have tried to silence them through the courts as well as in parliament but we will continue to make sure their voice is heard through the corridors of power.
“The NHS is fraying at the edges. To improve care and address the shortage, government must bring more people into nursing and keep them there by paying staff fairly.”
In the new ballot, the union will seek a country-wide mandate, allowing strikes in every NHS trust or NHS employer in England with RCN members.
For this, at least 50% of eligible members must vote and the majority must want strike action.
The ballot closes on 23 June, with the result expected in the following week.
The government has said there will be no improvement to the pay offer made in April, with a No 10 spokesman saying: “We have offered a fair and generous deal that the RCN themselves recommended to its members and subsequently accepted by the majority of other unions via the NHS staff council.
“We continue to think it’s important that all unions recognise that collective decision and it should be respected.”
Also today, a six-week ballot opens for more than 300,000 council and school support staff in England and Wales on whether they should also strike over pay.
The union, Unison, has called for a pay increase of 2% above inflation, claiming that since 2010 the value of local government pay has fallen by 25%.
The ballot is open to workers such as refuse collectors, social workers, teaching assistants, and librarians, with another ballot opening for Northern Ireland in August.
Unison general secretary Christina McAnea said: “These workers are truly dedicated but they’ve had enough. Going on strike is a huge step that isn’t taken lightly but many feel they have to make a stand.
“Employers can do far better, but ministers also need to step up to make sure local government is given the funding it needs, so staff get a decent wage and services are protected.”